// MIT License
//
// Copyright (c) 2017 Wesley Wickwire
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

struct RelativeVectorPointer<Offset: FixedWidthInteger, Pointee> {
    var offset: Offset
    mutating func vector(metadata: UnsafePointer<Int>, n: Int) -> UnsafeBufferPointer<Pointee> {
        return metadata.advanced(by: numericCast(offset))
            .raw.assumingMemoryBound(to: Pointee.self)
            .buffer(n: n)
    }
}

extension RelativeVectorPointer: CustomStringConvertible {
    var description: String {
        return "\(offset)"
    }
}
